Do you think that that's a thing with unipivots? I've heard that about Aro's before, also about the Audio Origami uni, I have a Morsch unipivot as well, and as you say it doesn't go particularly deep but it's sweet and detailed.
I've heard that several times, too.
In contrast to that, Michael Fremer states in his article about the Immedia RPM2 unipivot that a Rockport arm couldn't match the bass performance of the RPM2.
Noor could any other arm heard heard up to then.
The article is from 1997, either he hadn't heard THAT much by then in contrast to today.
But I have the RPM and from my somewhat limited XP this uni is quite impressive in bass performance, in comparison to, say, my Ekos for example.
I think I heard the Nottingham unis are also not at all bass-shy,
so as a shot into the blue it could be a relation between carbon as TA material and the specific bass performance result..?
No idea really, just as a generalisation uni makes no bass,
I'd say: no.
The article is an interesting read generally, the Aro is mentioned a few times as well,,for those interested, here:
http://www.stereophile.com/content/immedia-rpm-2-tonearm-page-4